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Optimization of flotation efficiency of phosphate minerals in mine tailings using polymeric depressants : experiments and machine learning

Alsafasfeh Ashraf, Alagha Lana, Alzidaneen Ala, Nadendla Venkata Sriram Siddhardh

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 4

art. no. 150477

EN

In this study, direct froth flotation experiments were conducted on silicate-rich phosphate tailing samples. The average grade of P2O5 in the flotation feed was 21.6% as determined using a combination of spectroscopic techniques including X-ray powder diffraction (XRD), mineral liberation analysis (MLA), and scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS). Two polymers were selected to promote the depression of silicates and enhance the flotation of phosphates: in-house synthesized hybrid polyacrylamide (Hy-PAM) and chitosan. Flotation efficiency of phosphates was evaluated at different flotation conditions including depressant type, depressant dosage, pH, and the flotation time. Results indicated that the optimum flotation efficiency of phosphate minerals (84.6% recovery at 28.6% grade of P2O5) was obtained when Hy-PAM was utilized at the studied range of pH and flotation time. All datasets produced from the flotation experiments were integrated within the framework of machine learning (ML) using artificial neural networks (ANNs). The ANN platform was trained, validated, and successfully employed to predict the process outcomes in relation to the pulp and reagents characteristics, which in turn were used to determine the optimum values of process variables. Coefficient of determination (R2), mean absolute error (MAE), and root-mean-square error (RMSE) were used as model indicators. Optimization results showed that the peak flotation performance could be achieved at higher dosages of both polymers. However, lower pH and shorter flotation time for Hy-PAM, and higher pH and longer flotation time for chitosan, were predicted to give the optimum process efficiency.

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The Behavior of Jordanian Oil Shale during Combustion Process from the El-Lajjun Deposit

Gougazeh Mousa, Alsaqoor Sameh, Borowski Gabriel, Alsafasfeh Ashraf, Hdaib Ismail I.

Journal of Ecological Engineering

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2022

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Vol. 23, nr 8

133--140

EN

The results of X-ray diffraction, thermogravimetric and FTIR spectroscopy analyses of mineral composition indicated that the El-Lajjun oil shale is principally composed of calcite, quartz with minor amounts of kaolinite), gypsum, and apatite. The obtained oil shale ash products at 830 °C and 1030 °C are dominated by lime, quartz, anhydrite, portlandite, gehlenite, and amorphous phases. The TGA weight loss curves clearly indicate that it occurred in the temperature range from 310 to 650 °C. The decomposition of oil shale carbonates was detected above 750°C. The functional groups in the organic material of oil shale are dominated by the aliphatic hydrocarbons, the semi-ash of which had diverse structures of polycyclic aromatic hydrocarbons. The most intensive of combustion occurred in the temperature range of 400–750 °C. In this temperature range, about 75 wt.% was accounted for the total mass loss.

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Oil Shale Ash as a Substitutional Green Component in Cement Production

Alsafasfeh Ashraf, Alawabdeh Mohammad, Alfuqara Diya, Gougazeh Mousa, Amaireh Mazen N.

Advances in Science and Technology. Research Journal

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2022

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Vol. 16, no 4

157--162

EN

The energy crisis is one of the major challenges confronting the cement industry today. Although non-renewable energy sources are becoming scarce, the presence of significant quantities of oil shale indicates its continued use as an energy source in the cement industry. However, significant environmental impacts may occur as a result of the large amount of Oil Shale Ash (OSA). As a result, the researchers are investigating alternative methods for recycling and reusing the OSA in a variety of applications. The purpose of this work was to use OSA as a green substitute component in cement production due to its high calcium oxide (CaO) content, which is the major component of cement clinkers. The chemical composition of OSA and Clinker samples were determined using X-ray fluorescence (XRF) and X-ray diffraction (XRD). OSA and clinker samples were combined in various ratios and then ground in a ball mill to obtain the desired grain size. The new blended products were prepared and tested at Lafarge factory's laboratories. The results indicated that by adding 10 % of OSA to the Clinker, the mixed product performed better than the reference sample. Additionally, using this percentage of OSA results in a 45 % reduction in the power consumption of the grinding process compared to the reference sample.